PHYTOPARASITIC NEMATODES ASSOCIATED WITH 3 TYPES OF BLUEBERRIES IN ARKANSAS

Research and commercial blueberry plantings were sampled in October 19 91 to determine the population densities and species of phytoparasitic nematodes associated with rabbiteye (Vaccinium ashei), southern highb ush (Vaccinium sp.), and highbush (V. corymbosum) blueberry cultivars and the sod middles between the blueberry rows. In the research planti ng at Clarksville, Arkansas, samples from the highbush cv. Bluecrop, t he southern highbush cv. Cooper and Gulf Coast, and the sod middles ha d similar numbers of total vermiform phytoparasitic nematodes (125-451 /250 cm(3) soil), whereas the samples from rabbiteye cv. Climax and Ti fblue had significantly lower numbers (4/250 cm(3)). The major nematod e species associated with blueberries and sod was Xiphinema americanum . In a research planting at Bald Knob, Arkansas, which contained Bluec rop and rabbiteye cultivars only, samples from Bluecrop and the sod ha d similar numbers (288 and 334/250 cm(3)), and the rabbiteye samples h ad significantly lower numbers (6-14/250 cm(3)). Xiphinema americanum was the major species found in the blueberry samples, whereas Mesocric onema ornate was the major species in the sod. Nematode population den sities and species distribution in commercial rabbiteye plantings in n ine counties in central and southwestern Arkansas varied greatly. The average population density for rabbiteye samples was 129/250 cm(3) and for sod was 577/250 cm(3). Weed infestations in the blueberry rows in the commercial plantings probably increased the population size and s pecies distribution.